Parameter

Category

Total population

(N = 440)

Group 1 (GA 38 weeks, N = 318)

Group 2 (GA 39 weeks, N = 122)

p-value

Freq.

%

Freq.

%

Freq.

%

Age

Mean, SD

32.90

4.81

32.91

5.01

32.89

4.27

0.976^t

Parity

2

209

47.5

138

43.4

71

58.2

0.016*

3

167

38.0

128

40.3

39

32.0

4+

64

14.5

52

16.4

12

9.8

Previous term labor

Median, P95

2

6

3

7

2

6

0.014*^M

Previous term labor (categorical)

0 - 1

19

4.3

12

3.8

7

5.7

0.054

2

204

46.4

138

43.4

66

54.1

>2

217

49.3

168

52.8

49

40.2

Previous preterm labor

None

402

91.4

289

90.9

113

92.6

0.560

1 or 2

38

8.6

29

9.1

9

7.4

SVD

None

321

73.0

224

70.4

97

79.5

0.062

1

54

12.3

46

14.5

8

6.6

2+

65

14.8

48

15.1

17

13.9

No. of c/s

2

279

63.4

187

58.8

92

75.4

0.003*

3

127

28.9

101

31.8

26

21.3

4+

34

7.7

30

9.4

4

3.3

Time interval from last c/s

Mean, SD

3.66

1.91

3.61

1.85

3.79

2.05

0.386^t (0.438^M)

Time interval from last c/s (categorical)

<2 years

50

11.4

36

11.3

14

11.5

0.964

2+ years

390

88.6

282

88.7

108

88.5

Gestational diabetes

No

336

76.4

245

77.0

91

74.6

0.588

Yes

104

23.6

73

23.0

31

25.4

Smoking status

Smoker

9

2.0

7

2.2

2

1.6

1.000^F

Non-smoker

431

98.0

311

97.8

120

98.4

Job status

Employed

86

19.5

68

21.4

18

14.8

0.116

Unemployed

354

80.5

250

78.6

104

85.2

BMI (kg/m²)

Mean, SD (range = 18.50, 52.00)

32.92

5.99

33.30

6.22

31.93

5.25

0.032*^t